Cambios geomorfológicos en ríos en roca tras inundaciones de baja frecuencia (Río Girona, Alicante)

Abstract

Bedrock rivers offer larger erosive resistance and therefore less incision capability as alluvial streams do. Changes occur very slowly and response to tectonics or eustathism might be not on phase at the different stream reaches. Along a bedrock gorge, different reaches show changes in hydraulic conditions and rather diverse responses on floods. According to the change in slope and transversal sections, erosive and agradational processes are fluctuating in relation to changes in velocity and load transport capacity. Due to the lack of alluvial floodplain, depth increase abruptly and accordingly stream power acquires a high geomorphic effectiveness. As it has been observed on the Barranco del Infierno after the occurrence of a low frequency flood, alluvial deposits have been strongly displaced, resulting in the emptiness of potholes and agradation at transfer reaches. The result of a medium to high magnitude flood is a radical change on fluvial landscape with large morphological modifications on bed and banks, bars and even on lateral slopes